Biomedical Research

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Research Article - Biomedical Research (2017) Volume 28, Issue 5

The significance of tissue doppler imaging in the diagnosis of left ventricular diastolic function

Abstract

Objective: Using tissue Doppler imaging (Tissue doppler imaging, TDI) to detect mitral annulus velocity in patients with hypertension and compared with blood flow Doppler method. This research was aimed to explore the new method to evaluate left ventricular diastolic function in patients with hypertension.

Methods: One hundred of hypertensive patients in our hospital were enrolled from March 2015 to June 2015. Mitral and tricuspid annular early diastolic velocity (Ea), and late diastole (Aa), and Ea/Aa of hypertension patients were detected by TDI. Early diastolic flow velocity (E), late diastolic velocity (A) and E/A were detected by mitral blood Doppler. And 50 healthy subjects were selected as the control group.

Conclusions: Compared to the blood flow Doppler technique, TDI is more sensitive detection of mitral annulus spectrum hypertension patients. Accurately reflecting the change of mitral annulus diastolic velocity plays important roles in the evaluation of left ventricular diastolic function.

Keywords

Tissue Doppler imaging; Left ventricular diastolic function

Introduction

Hypertension was a common disease in clinic, which was also
known as high blood pressure. Long-term high blood pressure
is a major risk factor for heart failure, coronary artery disease,
heart failure, stroke, and vision loss [1]. The severe disease can
lead to heart failure, mainly including contraction dysfunction.
The relaxation dysfunction usually happened before
contraction dysfunction. The early detection of diastolic
function change was valuable for clinic by preventing the
development of hypertension and establishing correct treatment
measures [2,3]. Left ventricular diastolic dysfunction is an
earlier alteration for many cardiovascular diseases [4]. Left
ventricular diastolic dysfunction might be caused by any kind
of heart disease that leads to pericardial effusion and/or
myocardial structural alteration [5].

Therefore, how to accurately evaluate left ventricular diastolic
function was important. Left ventricular diastolic properties
were first determined invasively using the rate of left
ventricular relaxation time constant, measurements of myocardial and chamber stiffness, and left ventricular pressure
decline. Currently, noninvasive evaluation of diastolic function
is applied in the day-to-day evaluation of left ventricular
function [6]. Pulsed-wave Doppler (PWD)-derived transmitral
inflow patterns are commonly used for assessment of left
ventricular diastolic function.

However, patients with left ventricular systolic dysfunction
often have variability in PWD-derived indices of left
ventricular diastolic dysfunction due to increases in LA
pressure, so they are preload-dependent [7]. Tissue Doppler
imaging (TDI)-derived early diastolic mitral annular velocity
(E’) and color M-mode (CMM) imaging flow propagation
velocity (Vp) have been reported to be less load-dependent
methods to assess LV relaxation [8]. TDI in evaluating left
ventricular diastolic function was investigated by comparing
the TDI with blood flow doppler method in this experiment.
Now report as follows.

Materials and Methods

Clinical data

100 cases patients with hypertension as observation group were
selected in March 2015 toJune 2015 in our hospital. Inclusion
criteria: when the blood pressure of a patient was in accordance
to these values such as SBP>140 MMHG, DBP>90 MMHG
according to the world health organization (WHO), it was
diagnosed as high blood pressure. Exclusion criteria: (1) the
patients with cardiovascular system function severely impaired; (2) the patients with physical state of memory; (3)
the patients with other cardiovascular disease. Research had
been completed before informing and consent of the patients.
The 50 normal volunteers were extracted as control group. 51
cases of male were selected as observation group. The age of
them was 26 to 57 years old, the average age was (41.6 ± 5.9)
years old; 28 cases of male were selected as control group. The
age of them was 23 ~ 57 year old, the average age was (42.9 ±
5.5) years old. There was no difference between the two groups
of patients with general information. It was comparable
(P>0.05). The results were shown in Table 1.

Project

Observation group (n=100)

Control group (n=50)

Statistical value

P value

gender (male/female)

51/49

28/22

0.3343

0.5631

age( ͞χ ± s, years old)

41.6 ± 5.9

42.9 ± 5.5

1.3006

0.1954

Heart rate ( ͞χ ± s, time/min)

72 ± 10

74 ± 8

1.2303

0.2205

BMI ( ͞χ ± s, kg/m2)

15.31 ± 5.97

16.66 ± 5.75

1.3215

0.1884

Table 1. The results of comparing two groups of patients in general information.

Methods

The patients inspected were token on the left side of the
hypothesis and breathed normally. Mitral valve mouth blood
flow spectrum was detected by conventional echocardiography
at first: Diastolic blood flow velocity during late and early
period (E, A) was detected when the sample volume was in
apex four cavity edge within the tip of the mitral valve. E/A
value was calculated. Mitral valve ring motion spectrum was
detected by adjusting the parameters of the instrument after
switched to TDI pattern: Diastolic blood flow velocity during
late and early period (Ea, Aa) was detected when the sample
volume was in apex four cavity edge within the tip of the
mitral valve inside and outside the ring. Ea/Aa value was
calculated. The instrument was checked by Aloka α7, color
Doppler ultrasound of Mindray DC-8 imported from Japan.

Observational index

Diastolic blood flow velocity during late and early period (E,
A) was detected and E/A value was calculated. Diastolic blood
flow velocity during late and early period (Ea, Aa) was
detected when the sample volume was in apex four cavity edge
within the tip of the mitral valve inside and outside the ring and
Ea/Aa was calculated.

Statistical methods

The experimental data was analyzed by SPSS19.0 professional
software and shown with mean ± standard deviation. It was
calculated by T test. The standard with P<0.05 was used to
determine whether the difference was statistically significant.

Results

Comparison on the E, A, E/A value in two groups of
patients

The E/A value of control group was between 1 and 2 by
doppler blood flow detection. 84 cases patients with E/A
abnormality in observation group were detected including 62
cases with E/A<1 (relaxation and tension abnormal with
diastolic function abate; RTADFA) and 22 cases with E/A≥2
(limitation abnormal with diastolic function abate; LADFA).
The E/A value of two kinds of patients were 0.59 ± 0.13 and
2.24 ± 0.17. Compared with the E/A value of control group
(1.23 ± 0.11), it had significant difference with statistically
significant (t=27.7129, 30.1541, P<0.05). The E/A value of 16
cases in observation group was detected between 1~2 (pseudo
normalization; PN). There was no statistically significant
difference with the observation group (t=1.3423,
P=1.3423>0.05). The results were shown in Table 2.

Group

E

A

E/A

Control group (n=50)

85.90 ± 9.21

67.78 ± 8.77

1.23 ± 0.11

Observation group (n=100)

RTADFA (n=62)

52.6 ± 10.11

87.12 ± 8.14

0.59 ± 0.13*

LADFA (n=22)

90.12 ± 8.68

40.91 ± 5.16

2.24 ± 0.17*

PN (n=16)

91.20 ± 7.12

69.17 ± 6.06

1.27 ± 0.08

Note: *The difference compared with the control group was statistically significant (P<0.05).

Table 2. Comparison on the E, A, E/A value in two groups of patients
(s, cm/s).

Comparison on the Ea, Aa, Ea/Aa value in two groups
of patients

The mitral valve ring motion spectrum of patients in control
group was detected by TDI with Ea>Aa and all >12 cm/s.
Mitral valve movement spectrum of patients in observation group were abnormal. 78 cases of patients with Ea<12 cm/s,
Ea/Aa<1 (RTADFA and PN) and Ea/Aa (0.59 ± 0.06/0.55 ±
0.04) were compared with the control group with Ea/Aa (1.38
± 0.07). The difference was statistically significant (t=64.2922,
44.9839, P<0.05); 22 cases of patients with Ea>Aa and all <8
cm/s (LADFA) and Ea/Aa (0.59 ± 0.06/0.55 ± 0.04) were
compared with the control group with Ea/Aa (15.12 ± 0.87
cm/s/10.12 ± 0.53 cm/s). The difference was statistically
significant (t=58.0992, 58.7353, P<0.05); the results were
shown in Table 3.

Group

Ea

Aa

Ea/Aa

Control group (n=50)

15.12 ± 0.87

10.12 ± 0.53

1.38 ± 0.07

Observation group (n=100)

RTADFA (n=62)

7.12 ± 0.91

11.34 ± 0.97

0.59 ± 0.06*

LADFA (n=22)

4.01 ± 0.31*

3.17 ± 0.24*

1.23 ± 0.11

PN (n=16)

5.91 ± 0.77

11.02 ± 0.75

0.55 ± 0.04*

Note: *The difference compared with the control group was statistically significant (P<0.05).

Table 3. Comparison on the Ea, Aa, Ea/Aa value in two groups of
patients (s, cm/s).

Observation on the spectrum image

The declining E peak and higher A peak of mitral valve ring
motion spectrum with E/A dropping less than 1 were appeared
when relaxation function was reduced in early period. When
diastolic function decreased aggravating, the increasing left
atrial pressure covered up the effect of peak E and A of mitral
valve blood flow spectrum by the anomaly early relaxation of
left ventricular diastolic. It made the examination results in
pseudo normalized. However, pseudo normalized was
identified by mitral valve ring motion spectrum with the E
peak value <A peak value. With the development of left
ventricular diastolic function reduced further into restrictive
filling, TDI on early spectrum of mitral valve ring motion
velocity was significantly lower than normal. The results of
test were shown in Figure 1.

Figure 1. The results of TDI.

Discussion

Hypertension was one of the most common diseases in clinic.
The main characteristics were the increasing of systemic
arterial systolic pressure and diastolic blood pressure. As a
kind of high risk factors of chronic disease, hypertension can
lead to a variety of cardiovascular complications [9]. Due to
the increasing of systemic arterial pressure and left ventricular
load, left ventricular systolic function was disorder by longterm
development of the disease and without effective control.
It caused heart failure at last. Several papers reported that
abnormal left ventricular diastolic function was happened
before abnormal systolic function [10,11]. Therefore, for
clinical patients with high blood pressure and without obvious
symptoms, timely and accurate assessment of left ventricular
diastolic function can effectively predict the occurrence of
heart failure. It was of great significance for clinical prevention
and treatment.

The left ventricular diastolic dysfunction was typed into
relaxation and tension abnormal with diastolic function abate,
limitation abnormal with diastolic function abate and pseudo
normalization, respectively according to the degree in clinic. It
was characterized by reducing left ventricular relaxation
function, pseudo normal filling function of left ventricular and
left ventricular dysfunction [12,13]. The left ventricular
function was assessed by the measurement of mitral valve
blood flow spectrum with echocardiography in past clinical
application. The ratio of Mitral diastolic early to late blood
flow velocity (E, A) was detected for the assessment of left
ventricular diastolic function. E/A value in normal was
between 1-2 [14,15]. When relaxation and tension abnormal
with diastolic function abate, the declining E peak and
increasing A peak of mitral valve blood flow spectrum were
appeared. The E/A value was not in the normal range. When
diastolic function decreased aggravating, the increasing left
atrial pressure covered up the effect of peak E and A of mitral
valve blood flow spectrum by the anomaly early relaxation of
left ventricular diastolic. It made the examination results in
pseudo normalized. As a result, it lead the mitral valve flow
spectrum can't make the right diagnosis [16,17].

TDI as a new clinical technique was developed in recent years.
It was also called myocardial tissue doppler imaging, which
was myocardial imaged by color doppler flow imaging
myocardial imaging technology. Thereby, the myocardial
function was observed directly. The diastolic function of heart
was assessed through the analysis of the motion state of
myocardial. Its principle was that as follows [18-20]: compared
with the vascular blood flow velocity of ventricular wall, blood
flow of the heart large blood vessels and heart cavity was much
faster. It can be characterized by two different signal intensity
when testing. Fast blood flow signal was filtered by DWI with
room wall of blood flow signals leaving. Observation of the
myocardial movement thus was realized. It help get rid of the
influence of left atrial pressure. A large number of clinical data
showed that [21] sensitivity of the results was as high as 90%
when Ea <8.5 cm/s and Ea/Aa <1 was set as the standard to
identify pseudo normal.

In this experiment, TDI mitral valve ring motion spectrum was
compared with echocardiographic mitral valve blood flow
spectrum. The results showed that the E/A change on mitral
valve flow spectrum can effectively instruct the diastolic
dysfunction of relaxation and tension abnormal with diastolic
function abate and limitation abnormal diastolic function abate
but E, A value and E/A on period of pseudo normal had no
obvious difference with the normal group. It was unable to
make effective diagnosis. Ea and Aa values of mitral valve ring
motion spectrum in the late diastolic dysfunction had
significant differences compared with normal levels. Ea/Aa
value in the early diastolic dysfunction and pseudo normal
period had obvious difference with control group. To sum up,
TDI can effectively identify each phase of the left ventricular
diastolic dysfunction and it was a reliable index for evaluation
of left ventricular diastolic function.

Li-Fang X. Assessment on left ventricular diastolic function in patients with diastolic heart failure and synchronicity of related research based on tissue doppler imaging. Nanchang University 2013; 22: 73-74.

Yu S, Wu Q, Bu J. Evaluation of the influence on left ventricular mechanical synchronicity in different parts of the pacemaker based on tissue doppler. Chinese J Ultrasound Med 2014; 30: 516-519.